Cutting chain structure



1952 c. J. FORBES CUTTING CHAIN STRUCTURE Fild April 21, 1949 INVENTOR BOman; J fbkfifs.

W if ANf/ii Patented Jan. 8, 1952 UNITED O F FICE' 2,581,58 f

CUTTING cHAnv STRUCTURE Charles J..Forbes,"'ferire Hautig Ind. fApplication April craggy, serialjNo. 88,882

This invention relates to holder, a bit, a complementary bearing memberand a clamp screw. i I

One chief object of the presentinvention is to simplify the bit holdingportion of the straddle link. i I

Another chief object of the present invention a is to simplify thepivotal connection between said link and its associatedconnecting link.

One feature oftheprese'nt invention resides in the broaching of theabutment portion of the straddle link to provide two overlappingparallel bores in one of which is seated the bit holder a cutting chainstruc ture comprised of connecting links alternated with and pivotallyconnected to adjacent straddle type links, each of the latter mounting ahooded adjacent connecting links.

apertures are circular.

2' Claims. (Cl. -74--254) spaced apart slightly greater than the"thickness H of the connecting links sothat said plates can accommodateand nest the adjacent ends of i Each side plate 10, see Fig. 6, iscorrespondingly apertured at H. On one side plate these In the otherthey are shouldered as at l2. .A tubular barrel pin l3 with bore l4therethrough is shouldered at IS in opposed relation. Bore, I4 iscountersunk at I6. Each side plate adjacent aperture =ll,-in-

cludes a longitudinally directed recess H in its outer face..Theserecessesorgrooves are longiwhen desired, being spotsecured bywelding in said receiving bore.

Another feature of the present-invention resides in providing in theplate portions of the straddle link, pivot receiving bores, which boresdetachably receive pivot forming tubular barrelmembers havingnon-rotative association with the said linkand mounting acountersunkheaded retainer that has a freeend disposed angularly of thebody portion, which free end is seated in registering notches in bothbarrel and link.

Other objects and features of the invention will be set forth more fullyhereinafter.

The full nature of the invention will be understood from theaccompanying drawings and the following description and claims:

In the drawings Fig. 1 is a side elevation of a portion of a cuttingchain, parts being broken and shown in longitudinal central section toshow same and other parts in greater detail.

Fig. 2 is a top plan view of the chain portion illustrated in Fig. 1.

Fig. 3 is a perspective view of the hooded bit holder.

Fig. 4 is a front elevation of the bearing member.

Fig. 5 is a perspective view of a diamond shape rhomboid type bit.

Fig. 6 is a sectional view taken on line 56 of Fig. 1 and in thedirection of the arrows.

In Figs. 1 and 2 of the drawings, A indicates adjacent connecting linkswhich are reduced at B between the ends, said ends being apertured at Cand bushed at D with hardened sleeves having a length, see Fig. 6,substantially that of the width of the connecting links.

The straddle link comprises side plates l tudinally aligned, see Fig. 2.

Preferably for strength 'retention they are not connected but they maybe if desired. A pin l8 with head I 9 to nest in countersink l6, seeFig; 6, is longer than the barrel and is disposed in the bore -,Mthereof and its free end 2|] is turned angularly to lie'in cross-slot 2iof the barrel -pivot and terminate in registering recess or groove I! asshown in Fig. 1; As shown in Figs. 2 and 6, no part of thepin; or barrelpivot projects beyond the outside faces of plates. Ill." Also thebarrelis rigidwith the "said plates by reason of shoulders and; I2,

respectively, inter-engaging" as shown in Figs. 1 and 6. Accordinglylinks A pivot upon fixed barrel pivots l3. Connection and disconnectioncan thus be readily effected.

The two plates l0 have inwardly directed upper lugs 22, see Fig. 2, andoutwardly directed lower flange portions 23, see Fig. 1. Each platethereabove includes a central slot 24 therethrough. One or both platesimmediately therebeneath may include inwardly directed lug 25 which inemergency may serve as a stop.

The two plates H? are suitably connected together by the upwardlyextending fore and aft directed body portion 26, the front face 21 ofwhich may be sloped slightly rearwardly. Extending downwardly andrearwardly therefrom is the threaded hole 28 to take dog clamp screw 29having bearing end 30.

Extending downwardly from the top of the body portion are two circularoutlined bores 81 and 32, see Fig. 1. These two overlap, as it were, seeFig. 2, and thus have communication for so much of their lengths as arein common. Bore 3| extends completely through the body. Bore 62referably does not.

Disposed in bore 32 is the hardened bearing member 33, see Figs. 1, 2and 4. It has a flattened or reduced rear face 34 and a grooved portion35 complementary to the associated portion of a cutting-bit 36 thatbears thereon. Herein such bit 36 is illustrated as of diamond rhomboidshape, and includes two cutting tips 31 diagonally disposed upon themajor diagonal.

Disposed in bore 3| is the shank 38 of the bit holder. Above the shankand rigid therewith is the fore and aft directed hood portion 39. Thefore portion 40 is peak-like and includes connected forwardly directededge portions 4| herein disposed in V-position to nest the adjacentposition of bit 36 as shown in Fig. 1. V

The rear face 42 is continued downwardly and rearwardly into the shankas at 43 and this portion is defined by the forwardly directed flangeportions 44. These are carried forwardly and merge with each other. Thisforms the lower rear seat portion for the trailing end of the bit.

Note that herein the shank is solid at its inner end 45. It may, ifdesired, be hollow and the upper end of such bore would open upon therear seat portion for powder discharge. Note also herein the'lower'endof the shank is substantial by cylindrical in outline so that rocking ofthe holder is prevented.

The trailing end of the hood prevents the holder dropping through thebore 3|. Should breakage occur stop 25 prevents shank dropping into thechain driving sprocket.

Immediately above the lower end 45 of the shank and coincident with thelower end of the bit seating socket therein there is provided aninclined bearing portion 46. This is engaged by end 30 of dog screw 29when the bit and holder is to be clamped in the body portion forcutting.

While the bearing member and holder are illustrated as disposing the bitin a plane coincident with the central longitudinal plane of thestraddle link and the chain, it is to be understood the bit may bedisposed at different angles to that plane as well understood in theart. In such cases bores 3| and 32 may be correspondingly inclined. Thusa single straddle link forging may be multiple broached at the desiredangle to form bores 3| and 32. Hence but one forging die is required forall straddle links.

While the invention has been illustrated and described herein in greatdetail, same is by way of example only and discloses the preferredembodiment of the invention, reference being had to the appended claims.

The invention claimed is:

1. In a cutting chain having alternated connecting and straddle links,the latter comprising spaced apart plate portions, the combination of acylindrical barrel pivot at each end of the straddle link bridging thespace between plates and extending through the adjacent end of aconnecting link and pivotally supporting same, said pivot having areduced square shoulder at one end, the straddle link having acomplementary shoulder to prevent relative rotation between "thestraddle link and the pivot, the barrel pivot having a bore therethroughwhich is enlarged at one end, and a radial slot in the other endcommunicating with the bore and extending to the barrel periphery, and apin seated in the bore and having at one end a head nested in the boreenlargement, the other end of the pin extending transversely of anddisposed in the radial slot, one of the link plates having spaced apartwall divided recesses in its face at its opposite ends registering withthe respective transverse REFERENCES CITED The following references areof record in the file of this patent: Y

UNITED STATES PATENTS Number Name Date 2,227,737 Osgood Jan. 7, 19412,255,856 Morrow Sept. 16, 1941 2,331,766 Cartlidge Oct. 12, 19432,347,329 Morrow Apr. 25, 1944 2,399,166 Cartlidge Apr. 30, 1946 ForbesJan. 11, 1949

